Communicable Disease

Communicable diseases kill more people and destroy more livelihoods than natural disasters and conflicts together. There are two ways in which communicable disease and disasters are related: 1) the outbreak of communicable disease may overwhelm community coping capacities and spark a disaster and 2) disaster events themselves are often feared to create situations where the spread of communicable disease is more likely.

Communicable diseases are caused by contamination hazards. Most of these diseases can be passed from one person to another. Methods of transmission include mucus, blood, bites (from insects or animals capable of transmitting the disease), breath, saliva and sexual contact.


  • Protect sources of clean water.
  • Vaccinate children against killer diseases.
    • Do not re-use needles.
  • Use clean and protected water sources.
    • Keep water clean and protected from contamination.
    • Use clean vessels and closed containers for transportation and storage.
    • Keep water clean during collection, transportation and storage.
    • Remove standing water that may attract insects and become contaminated.
    • Learn and practice reliable methods for purifying water.
  • Wash hands very well with soap.
  • Dispose of waste safely for humans, animals and the environment.
    • If latrines are not available, defecate well away from houses, water sources and places where children play.
    • Bury faeces immediately or cover with earth, sand or ash.
    • Locate trench and pit latrines away from water sources and keep them clean.
    • Make sure pit latrines are emptied or replaced regularly by trained people with mechanical and protective equipment, rather than manually.
  • Practice good sanitation
    • Dispose of any waste that attracts flies and insects.
    • Dispose of waste properly without contaminating water or soil.
  • Keep food clean and food safe for eating.

For airborne diseases:

  • Wash your hands very well using clean water and soap.
  • Always cover your coughs and sneezes.
  • When there are contagious diseases going around, keep a safe distance and avoid crowds if possible.
  • Use good ventilation.
  • Separate and care for your sick – Use only one caregiver – preferably a family member who is not at high risk and uses safety measures.
  • Other family members should monitor themselves daily for fever and cough.
  • Make sure that young children, pregnant women and people who have another disease receive medical care if they get sick.

For body-fluid borne diseases:

  • Wash your hands very well.
  • Practice safe sex.

For vector (animal) borne diseases:

  • Be careful handling and slaughtering animals.
  • Sleep under mosquito netting.

[Source: IFRC “Public awareness and public education for disaster risk reduction: key messages“]


Local and National Government

In each emergency situation, the lead agency for health is responsible for preparation for and response to a sharp increase in the numbers of cases of disease. To prepare for such an eventuality, it is essential that:

  • a surveillance system is put in place to ensure early warning of an increase in the incidence or numbers of cases of diseases;
  • an outbreak response plan is written for the disease – covering the resources, skills and activities required;
  • standard treatment protocols for the disease are available to all health facilities and agencies and that clinical workers are trained;
  • stockpiles of essential treatment supplies (medication and material) and laboratory sampling kits are available for the priority diseases, such as oral rehydration salts, intravenous fluids, vaccination material, tents, transport media and water purification supplies;
  • a competent laboratory is identified for confirmation of cases;
  • sources of relevant vaccines are identified in the event that a mass vaccination campaign is required, and that supplies of needles and syringes are adequate;
  • sources of additional treatment supplies are identified for non vaccine-preventable diseases in case of expansion and outbreak.
  • the availability and security of a cold chain are established.

There are a limited number of diseases with epidemic potential that pose a major threat to the health of a population facing an emergency situation. These diseases should be identified during the rapid assessment. In addition, the lead health agency should draw up a list of the main risk factors for outbreaks in the emergency-affected population. 

[Source: WHO “Communicable disease control in emergencies”]


Community Organization

There is great vulnerability in poorer and more remote communities to a range of communicable diseases including diarrhea, dengue, HIV/AIDS, and Avian Influenza. All of this amounts to a need for good prevention, preparedness and response systems.

Local leaders need to find ways to ensure that their communities can report outbreaks as soon as possible. Additionally, civil national societies should be as well a driving force in advocating change in disaster legislation in the country to improve disaster and communicable disease preparedness in their communities. Legal preparedness is ensuring that national laws and policies:

  • Facilitate fast mobilization and response to disaster response and communicable disease emergencies
  • Ensure good coordination and information exchange between different partners – local, national and international
  • Encourage good quality and accountability standards
  • Integrate key international and regional agreements and standards

[Source: IFRC “Legal Preparedness for Disasters and Communicable Disease Emergencies in Cambodia, Laos and Vietnam”]



Consider creating a or revising your current workplace’s Business Continuity Program.

Infectious diseases kill 13 million people every year. The outbreak of disease is certainly one among a range of hazards or threats that has the potential to cause a catastrophic disaster. Poverty is the primary cause of the spread of disease, while in turn, poor health exacerbates poverty. Therefore, communicable diseases have a profound effect on the lives of people, in particular vulnerable groups, and their overall development. [Source:IFRC]

With the significant movement of people in and out of countries, cities, and communities on a daily basis as the result of globalization and modernization trends, disease outbreaks have the potential to spread fast and cause significant negative impacts health, livelihoods, and well-being.

The outbreak of communicable diseases is also often presumed to be a high risk following the impacts of significant disaster events. Humanitarian emergencies often involve the displacement of large numbers of people. Those affected are frequently settled in temporary locations with high population densities, inadequate food and shelter, unsafe water, poor sanitation and lack of infrastructure. These circumstances can increase the risk of transmission of communicable diseases and other conditions, and can thus lead to increased mortality (death). In particular, diseases that have a tendency to become epidemic (referred to as epidemic-prone diseases) can be a major cause of morbidity (disease) and mortality during emergencies. Rapid detection and prompt response to epidemics among the affected population is a key priority during humanitarian crises. [Source: WHO]

However experience has often shown that increases in communicable diseases are dependent upon many factors and that disaster events alone are not a sufficient predictor of significant changes in communicable disease prevalence. Instead, the risks of outbreaks must be evaluated in the full context of exposure and vulnerability in disaster-affected communities through a comprehensive risk assessment. This allows the prioritization of interventions to reduce the most significant factors that may contribute to the spread of communicable diseases after a disaster.

Communicable diseases can be prevented through a variety of measures, such as:

  • public practice of good hygiene and sanitation
  • access to clean water
  • hand washing
  • vaccination
  • proactive surveillance
  • vector control

Communicable diseases are caused by contamination hazards. Examples are:

  • airborne (such as flu, typhus, tuberculosis, smallpox, measles, Severe Acute Respiratory Syndrome (SARS))
  • conveyed by body fluids (such as polio or HIV)
  • water borne (cholera, e. coli, dysentery)
  • food borne (such as salmonella, e. coli, listeria, hepatitis)
  • soil borne (such as anthrax)
  • vector borne (transmitted from animals to humans (such as the H5N1 avian flu virus, malaria, dengue or letospira).

[Source: IFRC “Public awareness and public education for disaster risk reduction: key messages“]

Communicable disease: It is an illness caused by an infectious agent, such as bacteria, virus, fungi or parasites and/or toxin. Most of these diseases can be passed from one person to another. Methods of transmission include mucus, blood, bites (from insects or animals capable of transmitting the disease), breath, saliva and sexual contact.

Glossary of communicable diseases preventable by vaccination:

Diphtheria: A bacterial disease marked by the formation of a false membrane, especially in the throat, which can cause death.

Haemophilus influenzae type b (Hib): A bacterial infection that may result in severe respiratory infections, including pneumonia, and other diseases such as meningitis.

Measles (also called Rubeolla): A contagious viral disease marked by the eruption of red circular spots on the skin.

Mumps: Acute contagious viral illness marked by swelling, especially of the parotid glands.

Pertussis (also called whooping cough): Bacterial infectious disease marked by a convulsive spasmodic cough, sometimes followed by a crowing intake of breath.

Poliomyelitis (also called polio): An acute infectious viral disease characterized by fever, paralysis, and atrophy of skeletal muscles.

Glossary of viral hepatitis:

Hepatitis A: A minor viral disease, that usually does not persist in the blood; transmitted through ingestion of contaminated food or water.

Hepatitis B: A viral disease transmitted by infected blood or blood products, or through unprotected sex with someone who is infected.

Hepatitis C: is a liver disease caused by the Hepatitis C virus (HCV), which is found in the blood of persons who have the disease. HCV is spread by contact with the blood of an infected person.

Glossary of other communicable diseases:

Avian influenza: Influenza viruses circulating in animals pose threats to human health. Humans can become ill when infected with viruses from animal sources, such as avian influenza virus subtypes H5N1 and H9N2 and swine influenza virus subtypes H1N1 and H3N2. The primary risk factor for human infection appears to be direct or indirect exposure to infected live or dead animals or contaminated environments.

Cholera: Cholera is an acute intestinal infection caused by ingestion of food or water contaminated with the bacterium Vibrio cholerae. It has a short incubation period, from less than one day to five days, and produces an enterotoxin that causes a copious, painless, watery diarrhea that can quickly lead to severe dehydration and death if treatment is not promptly given. Vomiting also occurs in most patients.

Malaria: Malaria is a life-threatening parasitic disease transmitted by mosquitoes. The parasite is transmitted from person to person through the bite of a female Anopheles mosquito, which requires blood to nurture her eggs.

Rabies: Rabies is a serious infection of the nervous system caused by a virus, known as Rabies virus. Rabies almost always results in death if a bite or scratch from a rabid animal (an animal infected with rabies) is not treated at the time of exposure and symptoms of an infection develop.

The Human Immunodeficiency Virus (HIV): HIV, is the virus that causes AIDS, the Acquired Immune Deficiency Syndrome in the late stages of infection. HIV is in the semen, vaginal fluid and blood of infected persons. Unprotected sex and shared needles or syringes with HIV or AIDS carriers are the main methods of disease transmission.

Tuberculosis (TB): Tuberculosis is a communicable disease that is caused by bacteria (germs) that attack the lungs or other parts of the body such as the kidney, spine or brain. If not treated properly, TB can be fatal. Other: Epidemic: The occurrence of disease within a specific geographical area or population that is in excess of what is normally expected. Pandemic: An epidemic occurring over a very large geographic area.


Epidemic: The occurrence of disease within a specific geographical area or population that is in excess of what is normally expected.

Pandemic: An epidemic occurring over a very large geographic area.

[Sources: World Health Organization (WHO) & Centers for Disease Control and Prevention (CDC)]